[Mailman-Developers] Strange Subject: handling

[mailman]

Good day!

I've started to use Mailman in my production environment.

I am impressed of its huge number of features !
Thank You for your job.

But I have discovered a bug (or I missed something in
mailman tuning).

When a message with certain Subject: arrived to list
from one of subscribers, the message silently dies
and nobody receives any warnings.
If I changed only Subject field of the message -
then the message had passed happily.
Moreover, if I've changed only encoding of a message
(from windows-1251 to koi8-r) the message passed again!

The Subject: is a Russian text encoded in the
following styles:



The 'Subject:' of the messages which had beed killed:

Outlook Express:

X-Mailer: Microsoft Outlook Express 6.00.2600.0000
Subject: =?windows-1251?B?IC0tIEVneXB0IC0tINHz8u737fvlIPbl7fsgIzE3IO7yIDEwLjA0Lg==?=
	=?windows-1251?B?MjAwMw==?=

Mozilla:

User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.0; ru-RU; rv:1.3) Gecko/20030312
Subject: -- Egypt -- =?windows-1251?Q?=D1=F3=F2=EE=F7=ED=FB=E5_=F6=E5=ED?=
  =?windows-1251?Q?=FB_=2317_=EE=F2_10=2E04=2E2003?=




The 'Subject:' of the messages which had beed happily posted:

Mozilla:

User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.0; ru-RU;
	rv:1.3) Gecko/20030312
Subject: [Test2] -- Egypt --
  =?koi8-r?b?89XUz97O2cUgw8XO2SAjMTcgz9QgMTAuMDQuMjAwMw==?=


Outlook Express:

X-Mailer: Microsoft Outlook Express 5.50.4522.1200
Subject: [Test2]  =?koi8-r?b?IC0tIEVneXB0IC0tIPPV1M/eztnFIA==?=
	=?koi8-r?b?w8XO2SAjMTcgz9QgMTAuMDQuMjAwMw==?=




So the questions is: Is this a bug or there is some tuning options for this?
Can I enable some additional debugging for the cases like this?

Mailman 2.1.1
Python 2.1.3
Debian 3.0r1 Woody

Best regards,
Maxim Yakubenko